Party-line telephone



Nov.v 22, 1927.

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la.v R.' lEATH.

PARTY LINE TELEPHONE 31a/minion EarLR.Ieat/v E. R. HEATH PARTY LINE TELEPHONE Filed June 1o. 1924I s sheets-sheet 3 www,

Patented Nov. 22, 1927.

UNITED STATES PATENT OFFICE.

EARL RAY HEATH, 'or COLUMBUS, onro, AssIeNon'ro annimmt-NATIONAL TELE- PHONE COMPANY, er coter/inns, oHIo, A CORPORATION or omo.

PARTYTLINE TELEPIONE.

Appncaneaaied rune 1o, 15524. serial No. 719,215.

This invention relates to improvements in party line telephonesystems, one object of the invention being the provision of a system by means ot which in party line service a series ot stations will be connected tothe exchange and provided With apparatus whereby upon the impression of a positive potential upon the line, all substations Will be disconnected from the line, i. e., the talliing and listening facilities oit" the instru ment.l Then, and because ot Vthe fact that the substations herein described are fitted With either the harmonic or synchromonic ringers, a particular frequency of alternating current, having an aiflinity only for one particular substation ringer, is impressed upon the line, said alternating current ringing the bell ot the substation desired, the ringer itself serving a dual :purpose: that ot (e) ringing the bell, and

' acting as a halt Wave rectilier of the alter- CII nating ringing current, Which resultant unidirectional current then is assed through a drop relay, (F in Fig. 1b), which connects the particular' substation signalled. This particular feature is of the greatest importance; as, first ot all,'by the simple application ot a positive potential to the line. all transmitters and receivers are disconnected from the line, and then, by the application of a ringing current, the substation desired is both signalled and connected with the one operation. y

ln order to fully understand the invention there will be illustrated -andfdesc'ribed at Vthe present vtime one method of puttingv the saine into effect and in which Figure l is diagrammatic View of the calling cord.

Figure 1F- is a similar view of the answeringl cord, and

Figure l" is a diagrammatic view of a sub-v station, it being understood that a'pli'irality ot' the same may be connected to the line and that all three of these ligures are to be considered jointly as the complete system.

ln order that the present invention may be more fully understood the description tol'- lowing Will be set out in vario-us stages and' a ypair of interlocking relays, and a fre,- quen'ey ringer serving as a 'rectifier ofthe ringing current for actuating one 'ofthe'se relays.

There is Aan assembly of four Contact springs r59,. 60, 104 and 109, on the polarized relay E, and when a pulsing voltage of a negative polarity is applied, the relay is opoperates to open these contacts. Relay F,

the connecting relay, operates toy release ythe action imposed by the operation of relay H.

v There is a reeiproeatingaction among the three mentioned relays, E, and H. If the reeciverK been the hook l5 at a time `when a negative .pulse is applied, `relay -F will be operated. On vthe contrary, if' the receiver -beo' the hook When a negative pulse is applied, relay H Will be operated. It 'a positive pulse 'be applied to relay E, armature E Will be deflected in the Vdirection D; and if the receiver beI on the hook,

relay H willbe-operated; there will be no action Whenthere'ceiver is oil' the hook, and relay E operated tothe direetionD.

The ringers M of all instruments are permanently connected across the lines and, they are of the harmonic or synchromonic type, the frequencies being the standard fre-l quencies in common use; as 16, 30, 42, 54 and 66 cycles per second.

The harmonie or synchronionic method of ringing thus being employed, there is mounted upon each ringer an assembly of two contact springs 113 and 1l tone of which is mounted fast `to vthe armature and is subjectA to themotion of same; this armature (being an integral part of the ringer and therefore, electrically stating, a .part ofthetrame, and the frame connected to that side ofthe line on ivhichthe ringing current is impressed) .fthroughzits rhythmic vibration, then passes a half -Wave unidirectional current, obtained from the alternating ringing current, out through the two contacts above enumerated to actuate the drop7 relay F.

A general outline of this. system follows :e

A receiver K is removed from its hook at a certain substation S Fig. 1b. The signal lamp L glows at the switchboard; operator answers by plugging in and a positive pulse is sent out automatically over the line. Relay E is operated in the direction D on all instruments. On the calling station there will be no movement except the deflection of relay E. In this manner all idle stations will be locked out.

Upon the completion of service, when the receiver is placed upon the hook, a negative pulse is sent out over the line. This pulse detlects relay E the direction C and operates relays F of all instruments, preparing them for the next call.

Onall outgoing calls from the exchange, a positive pulse is automatically sent out upon inserting answering plug P in the socket S. This pulse disconnects all instruments as previously explained and the operator only presses ringing key of particular frequency desired; which frequency, while ringing the bell of station desired, serves to operate relay F of that station, by means of the contact springs aforementioned, thus connecting the lines through to the talking and listening circuits of the instrument. The connecting of all instruments to the line is made automatic upon completion of service. In case the calling party should hang up before called party answers, the former controls this restoring action; otherwise each party controls the separate functions of the line involved.

A. restoring key P2 is also provided for emergency use by the operator.

A detailed explanation of the various eircuits will now be taken up.

,Subscriber calls operator.

Upon the removal of the receiver from the hook 15, the hook switch contacts are closed in the usual manner and current flows from negative battery B1, the conductor 1, line relay J', the conductor 2, the contacts 3 and 4 of relay J, the conductor 5, ring 6 of jack socket S, line 7, the conductor 8, the winding 9, of induction coil 9, the conductorV 10, the contact springs 11 and 12, the conductor 13, hook switch contacts 14 and 15, the conductor 16, transmitter 17, the conductor 18, conductor 19, line 20, tip 21, the conductor 22, and contact springs 23 and 24 of relay J, the conductor 25 to grounds G and G and positive battery B. This circuit energizes line relay J which lights the line lamp L from negative battery B1, the conductor 26, line lamp L, the conductor 27, contact springs 28 and 29 of relay J i', the conductor 30 to grounds G and G.

Operator plugs The line lamp L glows, and the operator plugs in, and current flows from negative battery B2, the conductor 31, winding 32 of relay B, the conductor 33, coil of relay A, the conductor 34, sleeve 35 of plug P', sleeve 36 of jack socket S, the conductor 37, cutL oli' relay coil J, the conductor 38 to grounds G and G5. This current energizes relay J, clearing the line at contacts 3 and 4 and 23 and 24. It also energizes supervisory relay A which prepares the way for the preliminary pulse to follow, and the supervisory circuits. It does not, however, energize relay B on account of an insufficient number of turns in the winding 32 of the relay. There is another winding 47 on relay B through which it will be energized, i. e., the path of the preliminary pulse. At the moment of the inserting of the plug, current iiows from plus contact 39 of rectifying relay R, the conductor 40,7the contacts 41 and 42 of relay C, the conductor 43, the contacts 44 andf45 of relay A, the conductor46, wind- 'ng 47 of relay B, the conductor 48, contacts 49 and'50 of relay B, the conductor 51, tip 52 of plug P, tip -21 of jack socket S, line 2G, the conductor 53, condenser 54. To oppose this charge upon the plates of condenser 54, a negative pulse flows from ground g2, the conductor 55, relay E, the conductor 56, to condenser 54. This pulse deflects relay E in the direction "D, closing contact springs 59 and 69 and as the pulse divides at the junction of the conductors 2O and 53, it follows the conductor 19, the conductor 1S, transmitter 17, the conductor 16, hook switch contact 15, and from hook contact 15 to Contact 57, the conductor 58, springs 59 and G0 vof relay E know closed, conductor 61,`relay H', the conductor 62, the conductor 63. This circuit as will be seen simply places relay coil H electrically in series with relay E; bridging the condenser for the moment of pulsing. The relay coil H will be energized momentarily and raises spring 11 to be engaged by the projecting 'hook F of the relay F, which disconnects thetalking and listening circuits of all the instruments whose receivers were not olf the hook at vthe moment of pulsing.

At the instrument where the call Vwas made and the receiver off the hook there can be no action other than a detlection ofarmature E', consequently the instrument remains connected to the line vfor its duration of service. This pulse flowing through winding 47 of relay B,energizes this relay; but the springs being relatively stiff, retard this action somewhat allowing an appre-` ciable period to elapse from the moment of the contacting` of Contact 52 with contact 21,

to the breaking of contacts 49 and 50. This period determines the length of the preliniinary pulse; and While the circuit through this Winding `47 ot coilB is broken, the arniature isnow suiiiciently close to theooil that the small current` flowing in WindingV 32 Will be enough' to complete the stroke and close the lines through to the talking circuit of the cord. As follows :-contacts 50 and 64 of relay B, the conductor 65, Winding 66,v

relay D, conductor 67 to kg/7 or positive battei-y B3Y and :tor the tip side of line; negative voltage oi'` battery B3, the conductor 68,

and 52, the conductor 51, and the contacts-r '50 and 64. The voice current arriving at coil 9 of induction coil 9, is induced in the other Winding 81 of the coil 9', and the voltage generated in this Winding is inipressed upon the receiver K, the circuit of which is closed by hook switch contacts 14 and 75, the conductor 76, receiver K, the conductor 77, spring contacts 78 and 79 of the relay H, the conductor 80, induction coil Winding 81, conductor 82, condenser 83, and conductor 84.

Supervision,

Relay A on being energized, closed a pair of' contacts 86 and 87 which yprepared the Way for Vthe supervisory lamp L2; as folloivs-f-ground g4, the conductor 85, the contacts 36 and 87 saine relay, the conductor i the positive pulse troni its pointlof contact'l conductor 121 to'rgg. Y This unidirectional 88, the contacts 89 and 99 'of relay D, the conductor 91. supervisory lainp L2, tothe negative battery/*1B4 and ground G6. This circuit is broken at contacts 89 and 99 of relay D if the receiver is off the hook, andv the lanip L2 extinguished, by this ineans.

The current flowing through windings 66 and 69 of relay D supplying` the battery B3 ,tothe line. en'eigiz-es this relay and besides clearing the supervisory :signal lanipvLZ, closes a circuit troni negative side of battery B3, the conductors 68 and. 91, contact springs 92 and 93, the conductor 94, relay C. the conductor 95 to ground This energizes the relay C, which prepares the Way for the pulse which must be applied to the tip oit line after the coinpletion of service. It reverses the polarity of current to be sent out att-er the subscriber hangs up., It breaks with the line (at 49) by breaking contacts 42 troni'41 and closing negative pulse at its ,point of YContact 49 Withthe line by clos-`V relay A in the answering cord and sinilocks out all stations onv the line,- r

ing contact 42 withL coiitact96`which is the negative terminus' of the pulsing voltage koriginatingat contacts 98; as, contacts 98,

conductor 97 and the' contactv9'6.

Upemtor. answers.

The operator throws the listening key H1,

which .connects her listening set across the line'and inquires for the number. This beingv given, a calling cord, Fig. 1, (the inate Aot the ransnering cordfused). is inserted into the jack Fig. 1, as requested. Current-7 now iioivs troni the batteryy B, the conductor 131, Winding 1320i relay C2, the conductor 133, relay C1, the conductor 134,

.sleeve 135 ofv plug P, sleeve 36 of jack-socket S to `cut-'oit' relay coil Jas previously cx- Y plained. This energizes relay C1, the saine lar circuits apply. The effectonrelay C2y is the saine as, on the relay B jin the answering cord. i Current now flows froin positiv-e contact 39 of relay R, the conductorl Y140, contacts 141 and y142, the conductor 143.

contacts 144 and 145, the yconductor 146. coil i 147, the conductor 148, contacts 149 and 150,

the conductor 151, tip 152, tov tip 21 ofline jack socket S, and out over the Called line as follows cnductors 20 and 53,' condenser 54. The opposite charge flows troni ground g2, conductorl 55. relay E, conductor 56, and condenser 54. The relay E is deiiectedin the direction of arrow D closing contact springs 59 and 60 which places relay H in series with the relay E as before. This pulse To select a given one, afbutton O corresponding tothe frequency necessary to ring the bell, is pushed. This frequency'having JI the" saine period as the ringer of the station requested,` causes the bell of thev called stationto ring. bell has vreached its inaxiinuniv stroke, coiitacts 113, 114 are periodically closed, and an unidirectional currentV Hows.

The resultant force, upon which the par ticular instrument selected depends for its connection, is taken -froin the alternating ringingcurrent generator G, as follows: 1

generator G, the conductork 117, vcontact springs 118. and 119 of ringing button O.

Vthe conductor170, .contacts171 and 172 of 'relay C2, the conductor 173ring 174 of plug P,contacts .6, of jacksocke't S, the conduc tors 7, 11()` and 112, spring contacts 113 and '114, conductors 115 and 106, the relay F, cons ductors 107, 63 andr 56, 'condenser 54, con-l ductors53 and 20, contact 27 jack socket S,

tip 152 of plug-P. vthe conductor 151, coi'i-y tacts v150'and 16'4of relay C2,the conductor 165, contacts 116 and 120 ofv button O, andv currentnoperates-relay Fand causes itt'o When fthe armature of the sion in spring 11 of the relay H to close the contacts 11 and 12, and 7 8 and 7 9.

It is to be noted that these spring con* tacts Will be closed only on the instrument selected; all others Will remain locked out until service is completed..

Oreille@ Darty responds.

W'hen the called party answers, the circuit is completed trein negative voltage of the battery B5 as follows: the battery B5, the Winding 169 of relay C4, the conductor 170, he contacts 122 and 123 of key P2, theV conductor 124, the contacts 125 and 119 ot the .button O, the conductor 1.70, contacts 171 and 172 olf relay C2, the conductor 173, contacts 174 and 6, .the conductors 7 and 8, coil 9, the conductor 10, contacts 1.1 and 12, the conductor 13, contacts 14 and the conductor 16, transmitter 17, the conductors 18, 19 and 20, contacts 21 and 152, the conductor 151, contacts 150 and 164, the conductor 165, contact springs 116 and 126 ot button O, the concuctor 127, contact springs 128 and 129 o'l' hey A 2, the conductor 130, Winding 166 o1 relay t to positive battery B5. This energizes the relay C? and breaks the circuit oi the .calling supervisory lainp L at contacts 189 and 190. 1t also closes a circuit trein negative side of the battery B5, the conductor 191, the contact springs 192 and 193 ot relay Ct, the conductor 194, the relay C3, the conductor 195 to gT; energizing the relay C3, which prepares the Way for the pulse which must be applied to the tipof line after thev completion of service. 1t opens `the positive pulsing potential from its point of Contact with the line aty the contacts 149 and 150, by opening the contacts 142 and 141, and closes the negative pulsing' voltage to its point of contact with the line, by closing contacts 142 and 196, this `being theA negative terminus of the pulsating voltage originating at the contacts 98, 97, 197 andV killed .subscriber Imag/S ay).

201 and 202 of therelay C, the conductorl 203 and conductor 133. This action places negative potential on both si es of the energized Winding of the relay C2 and vthis rela C2 releases. VIn doin.O4 so its contact' 150 closes with 149; and current follows this path the conductor 148, coil -147, the con-' ductor 146, the contacts 145 and 144 of the relay C, the conductor 143, the contacts 142 and 196 of the relay C3, to negative potential of 1l. By this time the relay CZhas become reenergized thus breaking` the contacts 149 and 150. Relay C3 also has released, but a moment later, however. vSo the negative pulse had already gone to connect the instruments, as follows znegative of relay R, the contact 98, the conductors 97 and 197, contacts 196 and 142 or" therelay C3, the conductor 143, the contacts 144 and 145 ot' the relay C, the conductor '146,' the 1Winding 147, the conductor 148, and the contacts 149 and 150 o'l the relay' C2, the conductor 151, tip 152, contact 21, the conductors and 53, condenser 54, conductor 5, relay E, and ground G2. rThe armatureV of the relay E is now detiected toward C.

V Therefore the current flows from conductors 20, 19 and 18, transmitter 17, the conductor 16, contacts 15 and 57, conductors 58, springs 59 and 104, conductors 105 and 106, the relay F, conductors 107 and 63, to conductor 56, thus energizing the relay F Which closesV the :station circuits at the contacts 11 and 12 and 78V and 79.

Subscriber bangs up (calling).

rIhe action ot the answering cor-d upon the hanging up ot the receiver by the callingl party is identical with that ot the calling coi'd and need not be taken up here. There is a contingency however, when the calling party may hang up before called party has answered, and this contingency must be taken care of. In orderto do this a pair of contacts have been placed upon each of the relays D and C, Fig. 1, so that when the calling party hangs up a positive potential maybe momentarily applied, as follows?- the ground gs, the contact springs 104 and 105, Fig. 19, the conductor 106, the contactsV 107 and 108 of the relay C, the conductors 109 and 170, and the coil 169 of therelay Ct, F ig. 1, the conductor 169 to negative side of battery This merely serves to energize the relay Cl so that' it may tune`- tion as it a. receiver had really been removed. This energization is made only troni the energizing ot' the contacts104 and 105 of the relay 1) and nntil the break Sli of the contactsf107 and 108 of the relay' C takes place. Y

vDz'scoaaacting 'party who failed. to hang up tbe receiver.

hook, alrey is provided in the cord circuit.

rhis key is shown iny the accompanying drawings as key P2. When the key P2 is operated, a negative pulse, originating at the relay R', 'the contact 98,*the conductors 97 and 197, contacts 204 and 128 ot the key Cil P2, the conductor 127,the-contacts 126 and 116, the conductors y164, contacts 165 and 150, the conductor 21, contacts 152 and 151, the conductors 20, 19 and 18, transmitter 17, the conductor 16, contacts 15 and 14, conductor 13, contacts 109 and 60, the conductor 61, the relay II, conductors 62 and 63, the relay E, conductor to the ground g2. rI'his energizes the relay I-I and disconnects the instrument at the contacts 11 and 12, and 78 and 79.

Signa/Z station with, rece/oer of hoo/c.

The station then may be signaled by using the correct ringing frequency required by the ringer as the line is now clear, and the bell will be rung bet'ore the springs 113 and 114 have contacted to energize the relay F as before stated.

What I claim as new is: y

1. In a party line telephone system, including an exchange station and substations, a ringer at each substation, means at the exchange station for impressing upon the line an alternating current ot a frequency having aitinity for a ringer at a selected substation, whereby said ringer will operate to ring its bell and also act as a half-wave rectifier of the alternating ringing current, and means operable by the resultant unidirectional current to connect the particular substation signaled.

2. A party `line telephone system, including means operable by the insertion of a plug to disconnect all substations from the lin-e, and means to send out on the line impulses of a predetermined character and means operable by such impulses to connect only a selected substation to the line.

3. A party line telephone system, including means operable by the insertion of a plug to disconnect all substations from the line, and means to send out on the line impulses of a predetermined character' and means operable by such impulses to connect only a selected substation to the line, said lastmentioned means being operable to sendout on the line an impulse having a characteristic different trom that of the tirst-mentioned impulse. i

1. A party line ytelephone system including an exchange and a plurality oit substations, a polarized relay, a pair of interlocl ing relays, a frequency ringing'connector, and cooperating means for said relays in each substation, means located in the exchange station for impressing' upon the line an electrical current of one characteristic and cooperable with polarized relays in all substations to disconnect the substations from the line, and a second means in the exchange station for impresing upon the line an electrical cu rent of different characteristic andhaving an attinity for a particular frequency ringing connector and cooperable with the latter, whereby one substation is connected at a time.

5. In a party line telephone system including an exchange station and a plurality ot substations connected in line, a polarized relay, a pair of interlocking relays, a frequency ringing connector andccoperating means for said relays, in each substation, a cord circuit including a plug and socket at the exchange station, two sources of el-ectricity of different'characteristics located at the exchange station, means forconnecting one of said sources with the polarized relays at the substations, whereby a single impulse is sent out-.on the line to voperate said last-mentioned relays to disconnect the substations from the line, and means located at the exchange station for controlling the operation of the ringing connectors, whereby a particular frequency ringing connector is actuated at a selected substation to connect the same to the line.

In testimony whereof I aiix my signature.

EARL RAY HEATH. 

